A male doctor set out to prove 'man flu' is real — and scientists are fuming

The term 'Man flu' is defined by the Oxford English Dictionary as "a cold or similar minor ailment as experienced by a man who is regarded as exaggerating the severity of the symptoms." Shutterstock

"Man Flu" is the British term for a whiny guy who's complaining about his not-so-serious cold symptoms.

The Christmas issue of the peer-reviewed medical journal The BMJ takes on the issue in a lighthearted article written by a Canadian professor who says he was "tired of being accused of over-reacting" to illnesses.

Though there is some truth to his claim that some men might be "immunologically inferior" to some women, the scientific research is not conclusive.

Another BMJ author who's written about "Man Flu" before was critical of this report. She said "they're citing bad science to stack up more bad science."

You could be forgiven for not being familiar with the term "Man Flu." The idea hails from Britain, where people have been accusing men of whining, laying around too much, and just generally over-complaining when they're sick.

The Oxford English Dictionary says man flu is a "humorous, informal" noun — a term not to be taken too seriously. It's code for a "cold or similar minor ailment as experienced by a man who is regarded as exaggerating the severity of the symptoms."

In other words, the man flu has nothing to do with seasonal influenza. This is simply a term for male whining about being a wee bit sick.

But Canadian professor Kyle Sue, who teaches family medicine at Memorial University of Newfoundland, says he was "tired of being accused of over-reacting" to illnesses. So, he set out to present the current science on man flu, in the Christmas edition of The BMJ, a legitimate, scientific journal known for its humorous and lighthearted December issues. It's never totally clear how seriously the BMJ expects us to take these studies: in past years they've covered why Rudolph's nose is red, and reviewed the entire history of zombie infections, in literature dating back to the 1500s, but the science behind the sillier content is still generally sound.

This year, Sue wanted to explore if men might be "immunologically inferior" to women. Could it be, Sue hoped, that men aren't wimpier than women, and instead, might have some kind of legitimate health claim to lounging on the couch when they're sick?

Science suggests there are some legitimate differences between male and female immune systems

It's possible that female hormones may make women more resilient and less susceptible to common illnesses. A small 2010 study Sue cited of 63 healthy people in Australia showed that premenopausal women had stronger immune responses to 'Rhinovirus' (a common cold) than men, a benefit that disappears after menopause.

Researchers also think that male testosterone isn't helping men's chances of coming down with a cold or flu in the first place. That's because testosterone can have a suppressive effect on the immune system. Men with higher levels of testosterone have been shown to benefit less from a flu shot, and one study of male foragers in Bolivia showed that their testosterone rates were lower than men in the US. Scientists think this might be a defense mechanism to help them fight off more pathogens in the wild.

Women also tend to live longer than men and that death disparity extends to the flu: Epidemiologists studying ten years of mortality data in the US (from 1997 to 2007) found that men were more likely to die from the flu than women. For instance, men ages 50-64 had a rate of influenza-associated death that was 2.95 times the corresponding rate among women.

But women also have more nerve receptors than men, so they feel pain more intensely, which should make them more sensitive to the symptoms of a common cold. And there could be simpler reasons for the perception that women get sick less often and recover faster than men. Studies consistently show women are better at one very simple disease-busting ritual: handwashing.

The science so far is inconclusive

While some of the studies Sue cites hinge on reputable, peer-reviewed sources like those mentioned above, many of them are taken from research on very small sample sizes. Other areas of his paper are based on inconclusive study results and self-reported surveys. Sue even cites one 2006 BMJ review that lambasted a British pinup magazine for suggesting (based on an online survey of 2,000 magazine readers) that 'man flu' was real.

Social Psychologist Petra Boynton, who authored that critical report, was livid to discover that her work was being cited to support the existence of a man flu. She says her 2006 article was specifically pointing out how press coverage of the so-called man flu was based on unscientific magazine surveys and not actual public health research. She told Business Insider on Twitter that it's "disappointing" to see so much media coverage of an unserious study.

"They're citing bad science to stack up more bad science," she wrote. "If they were out to prove 'man flu' is a real thing, from the review they've published I don't think they can," she wrote in a direct message, saying the study suffers from some seriously "selective reporting."

The author of the BMJ report, Kyle Sue, told Business Insider in an email, "I'm not paid for my research. It's all out of my own interest done in my own time, so I'm not sure if I'll manage to do any follow up studies! I'm hopeful researchers better than myself will, though!"

Sue makes a hard push for protecting his own man flu behaviors in his paper: "Lying on the couch, not getting out of bed, or receiving assistance with activities of daily living could also be evolutionarily behaviours that protect against predators," he writes.

Boynton says that kind of evolutionary psychology argument is flawed, and not rooted in evidence-based scientific research methods.

Men, if you must lie on the couch and complain when you're sick, please at least wash your hands before you rejoin the working world.

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